HPE LeftHand/StoreVirtual driver¶

The HPELeftHandISCSIDriver is based on the Block Storage service plug-in architecture. Volume operations are run by communicating with the HPE LeftHand/StoreVirtual system over HTTPS, or SSH connections. HTTPS communications use the python-lefthandclient, which is part of the Python standard library.

The HPELeftHandISCSIDriver can be configured to run using a REST client to communicate with the array. For performance improvements and new functionality the python-lefthandclient must be downloaded, and HP LeftHand/StoreVirtual Operating System software version 11.5 or higher is required on the array. To configure the driver in standard mode, see HPE LeftHand/StoreVirtual REST driver.

For information about how to manage HPE LeftHand/StoreVirtual storage systems, see the HPE LeftHand/StoreVirtual user documentation.

HPE LeftHand/StoreVirtual REST driver¶

This section describes how to configure the HPE LeftHand/StoreVirtual Block Storage driver.

System requirements¶

To use the HPE LeftHand/StoreVirtual driver, do the following:

Install LeftHand/StoreVirtual Operating System software version 11.5 or higher on the HPE LeftHand/StoreVirtual storage system.
Create a cluster group.
Install the python-lefthandclient version 2.1.0 from the Python Package Index on the system with the enabled Block Storage service volume drivers.

Supported operations¶

Create, delete, attach, and detach volumes.
Create, list, and delete volume snapshots.
Create a volume from a snapshot.
Copy an image to a volume.
Copy a volume to an image.
Clone a volume.
Extend a volume.
Get volume statistics.
Migrate a volume with back-end assistance.
Retype a volume.
Manage and unmanage a volume.
Manage and unmanage a snapshot.
Replicate host volumes.
Fail-over host volumes.
Fail-back host volumes.
Create, delete, update, snapshot, and clone generic volume groups.
Create and delete generic volume group snapshots.
Create a generic volume group from a group snapshot or another group.

When you use back end assisted volume migration, both source and destination clusters must be in the same HPE LeftHand/StoreVirtual management group. The HPE LeftHand/StoreVirtual array will use native LeftHand APIs to migrate the volume. The volume cannot be attached or have snapshots to migrate.

Volume type support for the driver includes the ability to set the following capabilities in the Block Storage API cinder.api.contrib.types_extra_specs volume type extra specs extension module.

hpelh:provisioning
hpelh:ao
hpelh:data_pl

To work with the default filter scheduler, the key-value pairs are case-sensitive and scoped with hpelh:. For information about how to set the key-value pairs and associate them with a volume type, run the following command:

$ openstack help volume type

The following keys require the HPE LeftHand/StoreVirtual storage array be configured for:

hpelh:ao
The HPE LeftHand/StoreVirtual storage array must be configured for Adaptive Optimization.

hpelh:data_pl
The HPE LeftHand/StoreVirtual storage array must be able to support the Data Protection level specified by the extra spec.
If volume types are not used or a particular key is not set for a volume type, the following defaults are used:
hpelh:provisioning
Defaults to thin provisioning, the valid values are, thin and full

hpelh:ao
Defaults to true, the valid values are, true and false.

hpelh:data_pl
Defaults to r-0, Network RAID-0 (None), the valid values are,
- r-0, Network RAID-0 (None)
- r-5, Network RAID-5 (Single Parity)
- r-10-2, Network RAID-10 (2-Way Mirror)
- r-10-3, Network RAID-10 (3-Way Mirror)
- r-10-4, Network RAID-10 (4-Way Mirror)
- r-6, Network RAID-6 (Dual Parity)

Enable the HPE LeftHand/StoreVirtual iSCSI driver¶

The HPELeftHandISCSIDriver is installed with the OpenStack software.

Install the python-lefthandclient Python package on the OpenStack Block Storage system.
```
$ pip install 'python-lefthandclient>=2.1,<3.0'
```
If you are not using an existing cluster, create a cluster on the HPE LeftHand storage system to be used as the cluster for creating volumes.

Make the following changes in the /etc/cinder/cinder.conf file:

# LeftHand WS API Server URL
hpelefthand_api_url=https://10.10.0.141:8081/lhos

# LeftHand Super user username
hpelefthand_username=lhuser

# LeftHand Super user password
hpelefthand_password=lhpass

# LeftHand cluster to use for volume creation
hpelefthand_clustername=ClusterLefthand

# LeftHand iSCSI driver
volume_driver=cinder.volume.drivers.hpe.hpe_lefthand_iscsi.HPELeftHandISCSIDriver

# Should CHAPS authentication be used (default=false)
hpelefthand_iscsi_chap_enabled=false

# Enable HTTP debugging to LeftHand (default=false)
hpelefthand_debug=false

# The ratio of oversubscription when thin provisioned volumes are
# involved. Default ratio is 20.0, this means that a provisioned capacity
# can be 20 times of the total physical capacity.
max_over_subscription_ratio=20.0

# This flag represents the percentage of reserved back-end capacity.
reserved_percentage=15

You can enable only one driver on each cinder instance unless you enable multiple back end support. See the Cinder multiple back end support instructions to enable this feature.

If the hpelefthand_iscsi_chap_enabled is set to true, the driver will associate randomly-generated CHAP secrets with all hosts on the HPE LeftHand/StoreVirtual system. OpenStack Compute nodes use these secrets when creating iSCSI connections.

Important

CHAP secrets are passed from OpenStack Block Storage to Compute in clear text. This communication should be secured to ensure that CHAP secrets are not discovered.

Note

CHAP secrets are added to existing hosts as well as newly-created ones. If the CHAP option is enabled, hosts will not be able to access the storage without the generated secrets.

Save the changes to the cinder.conf file and restart the cinder-volume service.

The HPE LeftHand/StoreVirtual driver is now enabled on your OpenStack system. If you experience problems, review the Block Storage service log files for errors.

Note

Previous versions implement a HPE LeftHand/StoreVirtual CLIQ driver that enable the Block Storage service driver configuration in legacy mode. This is removed from Mitaka onwards.